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Laugier F, Saumitou-Laprade P, Vernet P, Lepart J, Cheptou PO, Dufay M. Male fertility advantage within and between seasons in the perennial androdioecious plant Phillyrea angustifolia. ANNALS OF BOTANY 2023; 132:1219-1232. [PMID: 37930793 PMCID: PMC10902885 DOI: 10.1093/aob/mcad169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 08/29/2023] [Accepted: 10/26/2023] [Indexed: 11/07/2023]
Abstract
BACKGROUND AND AIMS Androdioecy, the co-occurrence of males and hermaphrodites, is a rare reproductive system. Males can be maintained if they benefit from a higher male fitness than hermaphrodites, referred to as male advantage. Male advantage can emerge from increased fertility owing to resource reallocation. However, empirical studies usually compare sexual phenotypes over a single flowering season, thus ignoring potential cumulative effects over successive seasons in perennials. In this study, we quantify various components of male fertility advantage, both within and between seasons, in the long-lived perennial shrub Phillyrea angustifolia (Oleaceae). Although, owing to a peculiar diallelic self-incompatibility system and female sterility mutation strictly associated with a breakdown of incompatibility, males do not need fertility advantage to persist in this species, this advantage remains an important determinant of their equilibrium frequency. METHODS A survey of >1000 full-sib plants allowed us to compare males and hermaphrodites for several components of male fertility. Individuals were characterized for proxies of pollen production and vegetative growth. By analysing maternal progeny, we compared the siring success of males and hermaphrodites. Finally, using a multistate capture-recapture model we assessed, for each sexual morph, how the intensity of flowering in one year impacts next-year growth and reproduction. KEY RESULTS Males benefitted from a greater vegetative growth and flowering intensity. Within one season, males sired twice as many seeds as equidistant, compatible hermaphroditic competitors. In addition, males more often maintained intense flowering over successive years. Finally, investment in male reproductive function appeared to differ between the two incompatibility groups of hermaphrodites. CONCLUSION Males, by sparing the cost of female reproduction, have a higher flowering frequency and vegetative growth, both of which contribute to male advantage over an individual lifetime. This suggests that studies analysing sexual phenotypes during only single reproductive periods are likely to provide inadequate estimates of male advantage in perennials.
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Affiliation(s)
- F Laugier
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, Montpellier, France
| | | | - P Vernet
- Univ Lille, CNRS, UMR 8198 - Evo-Eco-Paleo, F-59000 Lille, France
| | - J Lepart
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, Montpellier, France
| | - P-O Cheptou
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, Montpellier, France
| | - M Dufay
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, Montpellier, France
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Kiełkowska A, Dziurka M. Changes in polyamine pattern mediates sex differentiation and unisexual flower development in monoecious cucumber (Cucumis sativus L.). PHYSIOLOGIA PLANTARUM 2021; 171:48-65. [PMID: 32840866 DOI: 10.1111/ppl.13197] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 08/11/2020] [Accepted: 08/19/2020] [Indexed: 06/11/2023]
Abstract
Changes in the levels of polyamines are associated with fundamental physiological processes such as embryogenesis, induction of flowering, fruit development and ripening, senescence, and responses to environmental stresses, but the role of polyamines in sex differentiation and unisexual flower development has not been deeply studied. To extend the knowledge on the regulatory mechanisms of flowering in monoecious plant (producing unisexual flowers), we investigated the morphogenesis and free polyamine levels in Cucumis sativus during sex differentiation and unisexual flower development in vitro using histocytological and biochemical methods. As shown in our study, floral development in vitro was undisturbed and flowers of both sexes were produced. Sex differentiation relied on preventing the development of generative organs of the opposite sex, as we observed carpel repression in male flowers and stamen repression in female flowers. Pollen viability was negatively correlated with female flower development on the same node. Biochemical analysis revealed increased accumulation of aliphatic amines (tri, tetra-amines) in generative (flower buds and flowers) compare to vegetative (axillary buds and leaves) organs. Undifferentiated floral buds contained elevated levels of agmatine, cadaverine, spermidine and spermine. Sex differentiation was associated with significantly decreased levels of agmatine and cadaverine. Our results showed that female flowers contained higher levels of total polyamine than male flowers. The increased level of cadaverine was associated with macrogametogenesis and female flower maturation. Putrescine was important for male flower development. Such results support the hypothesis that aliphatic amines are involved in unisexual flower development.
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Affiliation(s)
- Agnieszka Kiełkowska
- Department of Plant Biology and Biotechnology, Faculty of Biotechnology and Horticulture, University of Agriculture in Krakow, Krakow, 31-425, Poland
| | - Michał Dziurka
- Polish Academy of Sciences, The Franciszek Górski Institute of Plant Physiology, Krakow, 30-239, Poland
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Moquet L, Lateur L, Jacquemart AL, De Cauwer I, Dufay M. Temporal dynamics of sexual dimorphism in a dioecious species. ANNALS OF BOTANY 2020; 126:471-480. [PMID: 32386315 PMCID: PMC7424764 DOI: 10.1093/aob/mcaa088] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Accepted: 05/04/2020] [Indexed: 06/01/2023]
Abstract
BACKGROUND AND AIMS Sexual dimorphism for floral traits is common in dioecious plant species. Beyond its significance for understanding how selection acts on plant traits through male vs. female reproductive function, sexual dimorphism has also been proposed as a possible risky characteristic for insect-pollinated plants, as it could drive pollinators to forage mostly on male plants. However, even though most flowering plant species spread their flowering across several weeks or months, the temporal variation of floral phenotypes and sexual dimorphism have rarely been investigated. METHODS We performed a survey of male and female plants from the dioecious generalist-pollinated Silene dioica (Caryophyllaceae) in a common garden experiment, over two consecutive flowering seasons. Flower number and floral size were measured each week, as well as pollen quantity and viability in male plants. KEY RESULTS Sexual dimorphism was found for all investigated floral traits, with males showing an overall higher investment in flower production and flower size. Males and females showed a similar temporal decline in flower size. The temporal dynamics of daily flower number differed between sexes, with males showing a peak in the middle of their flowering season, whereas flower production by females was quite stable over time. At the scale of the experimental population, both individual and floral sex ratios appeared to vary across the flowering season. Moreover, because the onset of flowering varied among plants, the magnitude of sexual dimorphism in floral size also fluctuated strongly through time. CONCLUSIONS Capturing male/female differences with only one temporal measurement per population may not be informative. This opens stimulating questions about how pollinator behaviour and resulting pollination efficiency may vary across the flowering season.
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Affiliation(s)
- L Moquet
- Univ. Lille, CNRS, Lille, France
- UMR PVBMT, Saint Pierre, La Réunion, France
- UCLouvain, Earth and Life Institute, Louvain-la-Neuve, Belgium
| | - L Lateur
- Univ. Lille, CNRS, Lille, France
| | - A-L Jacquemart
- UCLouvain, Earth and Life Institute, Louvain-la-Neuve, Belgium
| | | | - M Dufay
- Univ. Lille, CNRS, Lille, France
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, Univ Paul Valery Montpellier, Montpellier, France
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Chen M, Zuo XA. Effect of Pollen Limitation and Pollinator Visitation on Pollination Success of Haloxylon ammodendron (C. A. Mey.) Bunge in Fragmented Habitats. FRONTIERS IN PLANT SCIENCE 2019; 10:327. [PMID: 30984212 PMCID: PMC6448003 DOI: 10.3389/fpls.2019.00327] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 02/28/2019] [Indexed: 06/09/2023]
Abstract
Haloxylon ammodendron (C. A. Mey.) Bunge is an ecologically important species in arid regions. Pollen limitation may decrease plant reproduction due to low levels of pollen transfer and inadequate pollen receipt. In arid regions, pollen limitations of many plant species may be influenced by habitat fragmentation. However, whether pollen limitation and pollinator visitation affect the pollination success of H. ammodendron (Amaranthaceae) in fragmented habitats still needs further study. In this study, we calculated the pollen limitation in natural and fragmented habitats to estimate the effect of habitat fragmentation on pollen limitation. In different habitats, we investigated the relationship between the number of open flowers and pollinator visiting frequency. In addition, we examined how habitat fragmentation affects pollination success through the influence of pollinator visitation rate on seed set. Our results indicated that pollen limitation was the important limiting factor for seed set in fragmented and natural habitats. The results showed higher pollinator visitation rates resulted in a higher percentage of seeds in both habitats. In H. ammodendron, Apis mellifera was found to be the dominant pollinator. These results may support the assertion that plants evolve traits to attract pollinators and pollinators increase their visiting frequency to better exploit the floral resources. We also determined that outcrossing was dominant in the breeding system and that wind pollination played an important role in pollination success. This study aims to contribute to a better understanding of how environmental heterogeneity affects pollen limitation, pollinator visitation, and pollination success in arid regions.
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Tello J, Montemayor MI, Forneck A, Ibáñez J. A new image-based tool for the high throughput phenotyping of pollen viability: evaluation of inter- and intra-cultivar diversity in grapevine. PLANT METHODS 2018; 14:3. [PMID: 29339970 PMCID: PMC5759351 DOI: 10.1186/s13007-017-0267-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Accepted: 12/15/2017] [Indexed: 05/12/2023]
Abstract
BACKGROUND Low pollen viability may limit grapevine yield under certain conditions, causing relevant economic losses to grape-growers. It is usually evaluated by the quantification of the number of viable and non-viable pollen grains that are present in a sample after an adequate pollen grain staining procedure. Although the manual counting of both types of grains is the simplest and most sensitive approach, it is a laborious and time-demanding process. In this regard, novel image-based approaches can assist in the objective, accurate and cost-effective phenotyping of this trait. RESULTS Here, we introduce PollenCounter, an open-source macro implemented as a customizable Fiji tool for the high-throughput phenotyping of pollen viability. This tool splits RGB images of stained pollen grains into its primary channels, retaining red and green color fractionated images (which contain information on total and only viable pollen grains, respectively) for the subsequent isolation and counting of the regions of interest (pollen grains). This framework was successfully used for the analysis of pollen viability of a high number of samples collected in a large collection of grapevine cultivars. Results revealed a great genetic variability, from cultivars having very low pollen viability (like Corinto Bianco; viability: 14.1 ± 1.3%) to others with a very low presence of sterile pollen grains (Cuelga; viability: 98.2 ± 0.5%). A wide range of variability was also observed among several clones of cv. Tempranillo Tinto (from 97.9 ± 0.9 to 60.6 ± 5.9%, in the first season). Interestingly, the evaluation of this trait in a second season revealed differential genotype-specific sensitivity to environment. CONCLUSIONS The use of PollenCounter is expected to aid in different areas, including genetics research studies, crop improvement and breeding strategies that need of fast, precise and accurate results. Considering its flexibility, it can be used not only in grapevine, but also in other species showing a differential staining of viable and non-viable pollen grains. The wide phenotypic diversity observed at a species level, together with the identification of specific cultivars and clones largely differing in this trait, pave the way of further analyses aimed to understand the physiological and genetic causes driving to male sterility in grapevine.
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Affiliation(s)
- Javier Tello
- Instituto de Ciencias de la Vid y del Vino (CSIC, Gobierno de La Rioja, Universidad de La Rioja), Carretera de Burgos km 6, Finca La Grajera, 26007 Logroño, Spain
- Division of Viticulture and Pomology, Department of Crop Sciences, University of Natural Resources and Life Sciences Vienna (BOKU), Konrad Lorenz Straße 24, 3430 Tulln, Austria
| | - María Ignacia Montemayor
- Instituto de Ciencias de la Vid y del Vino (CSIC, Gobierno de La Rioja, Universidad de La Rioja), Carretera de Burgos km 6, Finca La Grajera, 26007 Logroño, Spain
| | - Astrid Forneck
- Division of Viticulture and Pomology, Department of Crop Sciences, University of Natural Resources and Life Sciences Vienna (BOKU), Konrad Lorenz Straße 24, 3430 Tulln, Austria
| | - Javier Ibáñez
- Instituto de Ciencias de la Vid y del Vino (CSIC, Gobierno de La Rioja, Universidad de La Rioja), Carretera de Burgos km 6, Finca La Grajera, 26007 Logroño, Spain
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Varga S, Soulsbury CD. Sexually-trimorphic interactions with colour polymorphism determine nectar quality in a herbaceous perennial. Sci Rep 2017; 7:45838. [PMID: 28374829 PMCID: PMC5379179 DOI: 10.1038/srep45838] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Accepted: 03/06/2017] [Indexed: 11/09/2022] Open
Abstract
Amongst gynodioecious plant breeding systems, there can exist intermediate morphs with a reduction in their male function (i.e. reduced number of functional anthers). Along with this sexual trimorphism, plants can also show floral colour polymorphism. Such intricate mixtures of phenotypes within a species may have complex effects on floral rewards. Floral rewards are known to vary between sexually dimorphic species and to a lesser extent between colour morphs. However, the interactive effect of sexual trimorphism and colour polymorphism is unexplored. We measured nectar's sugar content in the sexually trimorphic Geranium sylvaticum, a gynodioecious plant with a light/dark floral polymorphism. We found that nectar reward differed across genders and colour morphs. Results were not however consistent within the three genders; dark female and hermaphrodite flowers had higher sugar content than light morphs, whereas intermediate flowers did not. As expected, females and hermaphrodites had different nectar reward, with intermediate morphs being midway between the other genders. In intermediates, the sugar content was not related to the number of functional stamens. We show for the first time the existence of sex-specific differences between flower gender and colour morphs in nectar rewards. Our results demonstrate the importance of considering multiple and conflicting selection pressures to explain rewards.
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Affiliation(s)
- Sandra Varga
- School of Life Sciences, University of Lincoln, Joseph Banks Laboratories, Lincoln LN6 7TS, UK
| | - Carl D. Soulsbury
- School of Life Sciences, University of Lincoln, Joseph Banks Laboratories, Lincoln LN6 7TS, UK
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Varga S, Kytöviita MM. Light availability affects sex lability in a gynodioecious plant. AMERICAN JOURNAL OF BOTANY 2016; 103:1928-1936. [PMID: 27864260 DOI: 10.3732/ajb.1600158] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2016] [Accepted: 10/27/2016] [Indexed: 06/06/2023]
Abstract
PREMISE OF THE STUDY Sex lability (i.e., gender diphasy) in plants is classically linked to the larger resource needs associated with the female sexual function (i.e., seed production) compared to the male function (i.e., pollen production). Sex lability in response to the environment is extensively documented in dioecious species, but has been largely overlooked in gynodioecious plants. METHODS Here, we tested whether environmental conditions induce sex lability in the gynodioecious Geranium sylvaticum. We conducted a transplantation experiment in the field where plants with different sex expression were reciprocally transplanted between high light and low light habitats. We measured plants' reproductive output and sex expression over four years. KEY RESULTS Our results show that sex expression was labile over the study period. The light level at the destination habitat had a significant effect on sexual expression and reproductive output, because plants decreased their reproductive output when transplanted to the low light habitat. Transplantation origin did not affect any parameter measured. CONCLUSIONS This study shows that sex expression in Geranium sylvaticum is labile and related to light availability. Sexually labile plants did not produce more seeds or pollen, and thus, there was no apparent fitness gain in sexually labile individuals. Sex lability in gynodioecious plants may be more common than previously believed because detection of sex lability necessitates data on the same individuals over time, which is rare in sexually dimorphic herbaceous plants.
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Affiliation(s)
- Sandra Varga
- Department of Biological and Environmental Science, University of Jyvaskyla, P.O. Box 35 40014 Jyvaskyla, Finland
| | - Minna-Maarit Kytöviita
- Department of Biological and Environmental Science, University of Jyvaskyla, P.O. Box 35 40014 Jyvaskyla, Finland
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Habarugira I, Hendriks T, Quillet MC, Hilbert JL, Rambaud C. Effects of nuclear genomes on anther development in cytoplasmic male sterile chicories (Cichorium intybus L.): morphological analysis. ScientificWorldJournal 2015; 2015:529521. [PMID: 25861678 PMCID: PMC4377467 DOI: 10.1155/2015/529521] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Accepted: 02/24/2015] [Indexed: 12/04/2022] Open
Abstract
The Cichorium intybus flower development in fertile, cytoplasmic male sterility (CMS 524) and various phenotypes carrying the 524 male sterile cytoplasm was investigated macroscopically and by light microscopy. The development was similar in fertile and in male sterile florets up to meiosis, and then it was affected in anther wall structure and pollen grain development in male sterile floret. In the male sterile plants, the tapetum intrusion after meiosis was less remarkable, the microspores started to abort at vacuolate stage, the connective tissue collapsed, and endothecium failed to expand normally and did not undergo cell wall lignification, which prevented anther opening since the septum and stomium were not disrupted. Crosses undertaken in order to introduce the CMS 524 into two different nuclear backgrounds gave rise to morphologically diversified progenies due to different nuclear-mitochondrial interactions. Macroscopic and cytological investigations showed that pollen-donor plants belonging to Jupiter population had potential capacity to restore fertility while the CC line could be considered as a sterility maintainer.
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Affiliation(s)
- Ildephonse Habarugira
- UMR 1281, Stress Abiotiques et Différenciation des Végétaux Cultivés, Université Lille 1, Sciences et Technologies, 59655 Villeneuve-d'Ascq, France
- University of Rwanda-Collège of Education, P.O. Box 5039, Kigali, Rwanda
| | - Theo Hendriks
- UMR 1281, Stress Abiotiques et Différenciation des Végétaux Cultivés, Université Lille 1, Sciences et Technologies, 59655 Villeneuve-d'Ascq, France
- Laboratoire Evolution Ecologie Paléontologie, Bât SN2, Cité Scientifique, Université Lille 1, Sciences et Technologies, 59655 Villeneuve-d'Ascq, France
| | - Marie-Christine Quillet
- UMR 1281, Stress Abiotiques et Différenciation des Végétaux Cultivés, Université Lille 1, Sciences et Technologies, 59655 Villeneuve-d'Ascq, France
- Laboratoire Evolution Ecologie Paléontologie, Bât SN2, Cité Scientifique, Université Lille 1, Sciences et Technologies, 59655 Villeneuve-d'Ascq, France
| | - Jean-Louis Hilbert
- UMR 1281, Stress Abiotiques et Différenciation des Végétaux Cultivés, Université Lille 1, Sciences et Technologies, 59655 Villeneuve-d'Ascq, France
- Laboratoire Régional de Recherche en Agroalimentaire et Biotechnologie, Institut Charles Viollette, Bât SN2, Cité Scientifique, Université Lille 1, Sciences et Technologies, 59655 Villeneuve-d'Ascq, France
| | - Caroline Rambaud
- UMR 1281, Stress Abiotiques et Différenciation des Végétaux Cultivés, Université Lille 1, Sciences et Technologies, 59655 Villeneuve-d'Ascq, France
- Laboratoire Régional de Recherche en Agroalimentaire et Biotechnologie, Institut Charles Viollette, Bât SN2, Cité Scientifique, Université Lille 1, Sciences et Technologies, 59655 Villeneuve-d'Ascq, France
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Varga S. Effects of arbuscular mycorrhizal fungi and maternal plant sex on seed germination and early plant establishment. AMERICAN JOURNAL OF BOTANY 2015; 102:358-366. [PMID: 25784469 DOI: 10.3732/ajb.1400361] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
UNLABELLED • PREMISE OF THE STUDY Arbuscular mycorrhizal fungi usually enhance overall plant performance, yet their effects on seed germination and early plant establishment, crucial steps in plant cycles, are generally overlooked. In gynodioecious species, sexual dimorphism in these traits has been reported, with females producing seeds that germinate at a faster rate than seeds from hermaphrodites.• METHODS Using the gynodioecious plant Geranium sylvaticum, I investigated in a greenhouse experiment whether the presence of arbuscular mycorrhizal spores affects seed germination and early plant establishment, examining at the same time whether the sex of the mother producing the seeds also influences these parameters and whether sex-specific interactions between these two factors exist.• KEY RESULTS The presence of arbuscular mycorrhizal spores in the soil decreased seed germination, did not affect plant survival, but did increase plant growth. Moreover, no significant differences in seed traits were detected between the sexes of the plants producing the seeds.• CONCLUSIONS This study demonstrates that arbuscular mycorrhizal fungi may have contrasting effects for plants during early life stages and that mycorrhizal effects can take place even at the precolonization stage.
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Affiliation(s)
- Sandra Varga
- Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland
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Varga S, Kytöviita MM. Variable mycorrhizal benefits on the reproductive output of Geranium sylvaticum, with special emphasis on the intermediate phenotype. PLANT BIOLOGY (STUTTGART, GERMANY) 2014; 16:306-314. [PMID: 23870051 DOI: 10.1111/plb.12050] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Accepted: 04/19/2013] [Indexed: 06/02/2023]
Abstract
In several gynodioecious species, intermediate sex between female and hermaphrodite has been reported, but few studies have investigated fitness parameters of this intermediate phenotype. Here, we examined the interactions between plant sex and arbuscular mycorrhizal (AM) fungal species affecting the reproductive output of Geranium sylvaticum, a sexually polymorphic plant species with frequent intermediate sexes between females and hermaphrodites, using a common garden experiment. Flowering phenology, AM colonisation levels and several plant vegetative and reproductive parameters, including seed and pollen production, were measured. Differences among sexes were detected in flowering, fruit set, pollen production and floral size. The two AM species used in the present work had different effects on plant fitness parameters. One AM species increased female fitness through increasing seed number and seed mass, while the other species reduced seed mass in all sexes investigated. AM fungi did not affect intermediate and hermaphrodite pollen content in anthers. The three sexes in G. sylvaticum did not differ in their reproductive output in terms of total seed production, but hermaphrodites had potentially larger fathering ability than intermediates due to higher anther number. The ultimate female function--seed production--did not differ among the sexes, but one of the AM fungi used potentially decreased host plant fitness. In addition, in the intermediate sex, mycorrhizal symbiosis functioned similarly in females as in hermaphrodites.
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Affiliation(s)
- S Varga
- Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland
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Cytoplasmic male sterility contributes to hybrid incompatibility between subspecies of Arabidopsis lyrata. G3-GENES GENOMES GENETICS 2013; 3:1727-40. [PMID: 23935000 PMCID: PMC3789797 DOI: 10.1534/g3.113.007815] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
In crosses between evolutionarily diverged populations, genomic incompatibilities may result in sterile hybrids, indicating evolution of reproductive isolation. In several plant families, crosses within a population can also lead to male sterile progeny because of conflict between the maternally and biparentally inherited genomes. We examined hybrid fertility between subspecies of the perennial outcrossing self-incompatible Lyrate rockcress (Arabidopsis lyrata) in large reciprocal F2 progenies and three generations of backcrosses. In one of the reciprocal F2 progenies, almost one-fourth of the plants were male-sterile. Correspondingly, almost one-half of the plants in one of the four reciprocal backcross progenies expressed male sterility. In an additional four independent F2 and backcross families, three segregated male sterility. The observed asymmetrical hybrid incompatibility is attributable to male sterility factors in one cytoplasm, for which the other population lacks effective fertility restorers. Genotyping of 96 molecular markers and quantitative trait locus mapping revealed that only 60% of the plants having the male sterile cytoplasm and lacking the corresponding restorers were phenotypically male-sterile. Genotyping data showed that there is only one restorer locus, which mapped to a 600-kb interval at the top of chromosome 2 in a region containing a cluster of pentatricopeptide repeat genes. Male fertility showed no trade-off with seed production. We discuss the role of cytoplasm and genomic conflict in incipient speciation and conclude that cytoplasmic male sterility–lowering hybrid fitness is a transient effect with limited potential to form permanent reproductive barriers between diverged populations of hermaphrodite self-incompatible species.
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Dornier A, Dufay M. HOW SELFING, INBREEDING DEPRESSION, AND POLLEN LIMITATION IMPACT NUCLEAR-CYTOPLASMIC GYNODIOECY: A MODEL. Evolution 2013; 67:2674-87. [DOI: 10.1111/evo.12142] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Accepted: 04/16/2013] [Indexed: 11/26/2022]
Affiliation(s)
- Antoine Dornier
- Laboratoire de Génétique et Evolution des Populations Végétales; UMR-CNRS 8198, Université des Sciences et Technologies de Lille - Lille 1; France
| | - Mathilde Dufay
- Laboratoire de Génétique et Evolution des Populations Végétales; UMR-CNRS 8198, Université des Sciences et Technologies de Lille - Lille 1; France
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Perera PIP, Quintero M, Dedicova B, Kularatne JDJS, Ceballos H. Comparative morphology, biology and histology of reproductive development in three lines of Manihot esculenta Crantz (Euphorbiaceae: Crotonoideae). AOB PLANTS 2013; 5:pls046. [PMID: 23346343 PMCID: PMC3551401 DOI: 10.1093/aobpla/pls046] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Accepted: 11/15/2012] [Indexed: 05/26/2023]
Abstract
BACKGROUND AND AIMS Cassava (Manihot esculenta), a major food staple in the tropics and subtropics, thrives even in environments undergoing threatening climate change. To satisfy the increasing demand for crop improvement and overcome the limitations of conventional breeding, the introduction of inbreeding techniques such as the production of doubled haploid lines via androgenesis or gynogenesis offers advantages. However, comprehensive studies on cassava flower bud biology or structural development are lacking and precise structural and biological information is a prerequisite to enhance the efficiency of these techniques. METHODOLOGY The floral biology of three selected cassava lines was studied, focusing on morphology, phenology and pollen biology (quantity, viability and dimorphism). Histological studies were also conducted on microsporogenesis/microgametogenesis and megasporogenesis/megagameto-genesis to generate precise developmental data for these lines. PRINCIPAL RESULTS Male and female cyathia have distinct developmental phases. Pollen viability was high during immature stages of plant development; however, pollen mortality was common at later stages. Pollen trimorphism in male gametophytes towards the larger or smaller pollen size, as compared with normal size, was observed. Ten characteristic events were identified in male gametogenesis and six in female gametogenesis that were correlated with flower bud diameter. Male gametophyte diameter at different developmental stages was also determined. CONCLUSIONS Results indicate that the three lines did not differ significantly, except regarding a few morphological aspects such as plant height, flower colour and number of male cyathia. Pollen grains were initially viable, but viability decreased drastically at later stages of growth. Abnormal meiosis or mitosis triggered pollen trimorphism. The demonstrated sequential events of reproductive development generated valuable information at the cellular level, which will help close the current information gap for cassava improvement via breeding programmes and doubled haploid plant production.
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Affiliation(s)
- P. I. P. Perera
- Cassava Program, Agrobiodiversity Research Area, International Center for Tropical Agriculture, A.A. 6713 Cali, Colombia
| | - M. Quintero
- Cassava Program, Agrobiodiversity Research Area, International Center for Tropical Agriculture, A.A. 6713 Cali, Colombia
| | - B. Dedicova
- Biotechnology Unit, Agrobiodiversity Research Area, International Center for Tropical Agriculture, A.A. 6713 Cali, Colombia
| | - J. D. J. S. Kularatne
- Decision and Policy Analysis Research Area, International Center for Tropical Agriculture, A.A. 6713 Cali, Colombia
| | - H. Ceballos
- Cassava Program, Agrobiodiversity Research Area, International Center for Tropical Agriculture, A.A. 6713 Cali, Colombia
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14
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Caruso CM, Case AL, Bailey MF. The evolutionary ecology of cytonuclear interactions in angiosperms. TRENDS IN PLANT SCIENCE 2012; 17:638-643. [PMID: 22784826 DOI: 10.1016/j.tplants.2012.06.006] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2012] [Revised: 06/08/2012] [Accepted: 06/13/2012] [Indexed: 06/01/2023]
Abstract
Interactions between cytoplasmic and nuclear genomes have significant evolutionary consequences. In angiosperms, the most common cytonuclear interaction is between mitochondrial genes that disrupt pollen production (cytoplasmic male sterility, CMS) and nuclear genes that restore it (nuclear male fertility restorers, Rf). The outcome of CMS/Rf interactions can depend on whether Rf alleles have negative pleiotropic effects on fitness. Although these fitness costs are often considered to be independent of the ecological context, we argue that the effects of Rf alleles on fitness should be context dependent. Thus, measuring the cost of restoration across a range of environments could help explain geographic and phylogenetic variation in the distribution of Rf alleles and the outcome of CMS/Rf interactions.
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Affiliation(s)
- Christina M Caruso
- Department of Integrative Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
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15
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Caruso CM, Case AL. TESTING MODELS OF SEX RATIO EVOLUTION IN A GYNODIOECIOUS PLANT: FEMALE FREQUENCY COVARIES WITH THE COST OF MALE FERTILITY RESTORATION. Evolution 2012; 67:561-6. [DOI: 10.1111/j.1558-5646.2012.01798.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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16
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De Cauwer I, Arnaud JF, Klein EK, Dufay M. Disentangling the causes of heterogeneity in male fecundity in gynodioecious Beta vulgaris ssp. maritima. THE NEW PHYTOLOGIST 2012; 195:676-687. [PMID: 22691102 DOI: 10.1111/j.1469-8137.2012.04191.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Variation among individuals in reproductive success is advocated as a major process driving evolution of sexual polymorphisms in plants, such as gynodioecy where females and hermaphrodites coexist. In gynodioecious Beta vulgaris ssp. maritima, sex determination involves cytoplasmic male sterility (CMS) genes and nuclear restorers of male fertility. Both restored CMS and non-CMS hermaphrodites co-occur. Genotype-specific differences in male fitness are theoretically expected to explain the maintenance of cytonuclear polymorphism. Using genotypic information on seedlings and flowering plants within two metapopulations, we investigated whether male fecundity was influenced by ecological, phenotypic and genetic factors, while taking into account the shape and scale of pollen dispersal. Along with spatially restricted pollen flow, we showed that male fecundity was affected by flowering synchrony, investment in reproduction, pollen production and cytoplasmic identity of potential fathers. Siring success of non-CMS hermaphrodites was higher than that of restored CMS hermaphrodites. However, the magnitude of the difference in fecundity depended on the likelihood of carrying restorer alleles for non-CMS hermaphrodites. Our results suggest the occurrence of a cost of silent restorers, a condition supported by scarce empirical evidence, but theoretically required to maintain a stable sexual polymorphism in gynodioecious species.
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Affiliation(s)
- I De Cauwer
- Laboratoire de Génétique et Évolution des Populations Végétales, UMR CNRS 8198, Bâtiment SN2, Université des Sciences et Technologies de Lille - Lille 1, F-59655 Villeneuve d'Ascq Cedex, France
- Present address: Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK
| | - J-F Arnaud
- Laboratoire de Génétique et Évolution des Populations Végétales, UMR CNRS 8198, Bâtiment SN2, Université des Sciences et Technologies de Lille - Lille 1, F-59655 Villeneuve d'Ascq Cedex, France
| | - E K Klein
- INRA, UR 546, Biostatistique et Processus Spatiaux, Domaine St Paul, Site Agroparc, F-84914 Avignon Cedex 9, France
| | - M Dufay
- Laboratoire de Génétique et Évolution des Populations Végétales, UMR CNRS 8198, Bâtiment SN2, Université des Sciences et Technologies de Lille - Lille 1, F-59655 Villeneuve d'Ascq Cedex, France
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17
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Roumet M, Ostrowski MF, David J, Tollon C, Muller MH. Estimation of mating system parameters in an evolving gynodioecous population of cultivated sunflower (Helianthus annuus L.). Heredity (Edinb) 2012; 108:366-74. [PMID: 21915147 PMCID: PMC3313044 DOI: 10.1038/hdy.2011.79] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2011] [Revised: 07/22/2011] [Accepted: 08/02/2011] [Indexed: 11/09/2022] Open
Abstract
Cultivated plants have been molded by human-induced selection, including manipulations of the mating system in the twentieth century. How these manipulations have affected realized parameters of the mating system in freely evolving cultivated populations is of interest for optimizing the management of breeding populations, predicting the fate of escaped populations and providing material for experimental evolution studies. To produce modern varieties of sunflower (Helianthus annuus L.), self-incompatibility has been broken, recurrent generations of selfing have been performed and male sterility has been introduced. Populations deriving from hybrid-F1 varieties are gynodioecious because of the segregation of a nuclear restorer of male fertility. Using both phenotypic and genotypic data at 11 microsatellite loci, we analyzed the consanguinity status of plants of the first three generations of such a population and estimated parameters related to the mating system. We showed that the resource reallocation to seed in male-sterile individuals was not significant, that inbreeding depression on seed production averaged 15-20% and that cultivated sunflower had acquired a mixed-mating system, with ∼50% of selfing among the hermaphrodites. According to theoretical models, the female advantage and the inbreeding depression at the seed production stage were too low to allow the persistence of male sterility. We discuss our methods of parameter estimation and the potential of such study system in evolutionary biology.
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Affiliation(s)
- M Roumet
- UMR AGAP 1334, INRA, Montpellier, Mauguio, France
| | | | - J David
- UMR AGAP 1334, INRA, Montpellier, Mauguio, France
| | - C Tollon
- UMR AGAP 1334, INRA, Montpellier, Mauguio, France
| | - M-H Muller
- UMR AGAP 1334, INRA, Montpellier, Mauguio, France
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18
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De Cauwer I, Dufay M, Hornoy B, Courseaux A, Arnaud JF. Gynodioecy in structured populations: understanding fine-scale sex ratio variation in Beta vulgaris ssp. maritima. Mol Ecol 2011; 21:834-50. [PMID: 22211480 DOI: 10.1111/j.1365-294x.2011.05414.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Natural selection, random processes and gene flow are known to generate sex ratio variations among sexually polymorphic plant populations. In gynodioecious species, in which hermaphrodites and females coexist, the relative effect of these processes on the maintenance of sex polymorphism is still up for debate. The aim of this study was to document sex ratio and cytonuclear genetic variation at a very local scale in wind-pollinated gynodioecious Beta vulgaris ssp. maritima and attempt to elucidate which processes explained the observed variation. The study sites were characterized by geographically distinct patches of individuals and appeared to be dynamic entities, with recurrent establishment of distinct haplotypes through independent founder events. Along with substantial variation in sex ratio and unexpectedly low gene flow within study sites, our results showed a high genetic differentiation among a mosaic of genetically distinct demes, with isolation by distance or abrupt genetic discontinuities taking place within a few tens of metres. Overall, random founder events with restricted gene flow could be primary determinants of sex structure, by promoting the clumping of sex-determining genes. Such high levels of sex structure provide a landscape for differential selection acting on sex-determining genes, which could modify the conditions of maintenance of gynodioecy in structured populations.
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Affiliation(s)
- Isabelle De Cauwer
- Laboratoire de Génétique et Évolution des Populations Végétales, FRE CNRS 3268, Bâtiment SN2, Université des Sciences et Technologies de Lille - Lille 1, F-59655 Villeneuve d'Ascq Cedex, France.
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19
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De Cauwer I, Arnaud JF, Courseaux A, Dufay M. Sex-specific fitness variation in gynodioecious Beta vulgaris ssp. maritima: do empirical observations fit theoretical predictions? J Evol Biol 2011; 24:2456-72. [PMID: 21955089 DOI: 10.1111/j.1420-9101.2011.02380.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
In gynodioecious species, in which hermaphroditic and female plants co-occur, the maintenance of sexual polymorphism relies on the genetic determination of sex and on the relative fitness of the different phenotypes. Flower production, components of male fitness (pollen quantity and pollen quality) and female fitness (fruit and seed set) were measured in gynodioecious Beta vulgaris spp. maritima, in which sex is determined by interactions between cytoplasmic male sterility (CMS) genes and nuclear restorers of male fertility. The results suggested that (i) female had a marginal advantage over hermaphrodites in terms of flower production only, (ii) restored CMS hermaphrodites (carrying both CMS genes and nuclear restorers) suffered a slight decrease in fruit production compared to non-CMS hermaphrodites and (iii) restored CMS hermaphrodites were poor pollen producers compared to non-CMS hermaphrodites, probably as a consequence of complex determination of restoration. These observations potentially have important consequences for the conditions of maintenance of sexual polymorphism in B. vulgaris and are discussed in the light of existing theory on evolutionary dynamics of gynodioecy.
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Affiliation(s)
- I De Cauwer
- Laboratoire de Génétique et Évolution des Populations Végétales, FRE CNRS 3268, Bâtiment SN2, Université des Sciences et Technologies de Lille - Lille 1, Villeneuve d'Ascq Cedex, France.
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20
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Garraud C, Brachi B, Dufay M, Touzet P, Shykoff JA. Genetic determination of male sterility in gynodioecious Silene nutans. Heredity (Edinb) 2011; 106:757-64. [PMID: 20808324 PMCID: PMC3186230 DOI: 10.1038/hdy.2010.116] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2010] [Revised: 07/30/2010] [Accepted: 07/30/2010] [Indexed: 11/08/2022] Open
Abstract
Gynodioecy, the coexistence of female and hermaphrodite plants within a species, is often under nuclear-cytoplasmic sex determination, involving cytoplasmic male sterility (CMS) genes and nuclear restorers. A good knowledge of CMS and restorer polymorphism is essential for understanding the evolution and maintenance of gynodioecy, but reciprocal crossing studies remain scarce. Although mitochondrial diversity has been studied in a few gynodioecious species, the relationship between mitotype diversity and CMS status is poorly known. From a French sample of Silene nutans, a gynodioecious species whose sex determination remains unknown, we chose the four most divergent mitotypes that we had sampled at the cytochrome b gene and tested by reciprocal crosses whether they carry distinct CMS genes. We show that gynodioecy in S. nutans is under nuclear-cytoplasmic control, with at least two different CMSs and up to four restorers with epistatic interactions. Female occurrence and frequency were highly dependent on the mitotype, suggesting that the level of restoration varies greatly among CMSs. Two of the mitotypes, which have broad geographic distributions, represent different CMSs and are very unequally restored. We discuss the dynamics of gynodioecy at the large-scale meta-population level.
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Affiliation(s)
- C Garraud
- Laboratoire Ecologie, Systématique et Evolution, UMR 8079 Univ Paris-Sud, Orsay, France.
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21
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De Cauwer I, Arnaud JF, Schmitt E, Dufay M. Pollen limitation of female reproductive success at fine spatial scale in a gynodioecious and wind-pollinated species, Beta vulgaris ssp. maritima. J Evol Biol 2010; 23:2636-47. [PMID: 21040067 DOI: 10.1111/j.1420-9101.2010.02119.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In sexually polymorphic plants, the spatial distribution of sexes is usually not random. Local variation in phenotype frequencies is expected to affect individual fitness of the different phenotypes. For gynodioecious species, with co-occurrence of hermaphrodites and females, if sexual phenotypes are structured in space and pollen flow is spatially restricted, local pollen availability should vary among patches. Female fitness may thus be low when hermaphrodites are locally rare. To test this hypothesis, we analysed how the reproductive output of females varied among patches within two natural study sites of the gynodioecious wind-pollinated Beta vulgaris ssp. maritima. Plants growing in female-biased areas and experiencing pollen limitation were found to have low fruit and seed sets but did not reallocate resources towards better offspring. Our results show that fine-scale processes influence individual fitness and the evolution of sex ratio in sexually polymorphic plants.
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Affiliation(s)
- I De Cauwer
- Laboratoire de Génétique et Évolution des Populations Végétales, FRE CNRS 3268, Bâtiment, Université des Sciences et Technologies de Lille - Lille 1, Villeneuve d'Ascq Cedex, France.
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22
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Delph LF, Bailey MF. The nearness of you: the effect of population structure on siring success in a gynodioecious species. Mol Ecol 2010; 19:1520-2. [PMID: 20456237 DOI: 10.1111/j.1365-294x.2010.04587.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Theoretically, both balancing selection and genetic drift can contribute to the maintenance of gender polymorphism within and/or among populations. However, if strong differences exist among genotypes in the quantity of viable gametes they produce, then it is expected that these differences will play an important role in determining the relative frequency of the genotypes and contribute to whether or not such polymorphism is maintained. In this issue, De Cauwer et al. (2010) describe an investigation of gynodioecious wild sea beet, which in addition to containing females, contain two types of hermaphrodites: restored hermaphrodites carrying a cytoplasm that causes pollen sterility and a nuclear gene that restores pollen fertility, and hermaphrodites without the sterilizing cytoplasm. The results show that restored hermaphrodites, who have relatively low pollen viability, achieve disproportionately high siring success simply because of where they are located in a patchy population (Fig. 1). Notably, these individuals tend to be close to females because of the genetics of sex determination. These results indicate that population structure caused by drift processes can have an unexpectedly large effect on the fitness of these low quality hermaphrodites, thereby contributing in the short term to the maintenance of gynodioecy in this population. While these results indicate that population structure caused by drift processes can have a large effect on the relative fitness of genetic variants, whether these effects promote or discourage the maintenance of polymorphism in the long term is still up for debate.
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Affiliation(s)
- Lynda F Delph
- Department of Biology, 1001 East Third Street, Indiana University, Bloomington, IN 47405, USA.
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23
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Case AL, Caruso CM. A novel approach to estimating the cost of male fertility restoration in gynodioecious plants. THE NEW PHYTOLOGIST 2010; 186:549-557. [PMID: 20180910 DOI: 10.1111/j.1469-8137.2010.03199.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
*In many gynodioecious plants, sex is determined by cytoplasmic male sterility genes (CMS) and nuclear male fertility restorers (Rf). Models predict that the costs of restoration are important determinants of population sex ratios. However, current approaches to the estimation of these costs require prior identification of CMS genotypes, information that is available for few species. *We tested a novel approach to estimating the cost of restoration in natural populations without determining CMS or Rf genotypes. We used estimates of pollen viability and offspring sex ratios from open- and hand-pollinated families of Lobelia siphilitica to test whether the cost of restoration, expressed as low pollen viability, is higher in populations with more females. *Among populations with CMS, we found that variation in pollen viability was higher in small populations with more females, as expected if the proportion of females within populations increases with the maximum cost of restoration. In controlled crosses, families with low pollen viability also produced fewer females, suggesting that variation in viability is primarily determined by the number and frequency of Rf alleles carried. *This approach to estimating the cost of restoration can be applied to other cytonuclear gynodioecious species, offering new opportunities for testing gynodioecy models in the wild.
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Affiliation(s)
- Andrea L Case
- Department of Biological Sciences, Kent State University, Kent, OH, USA.
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24
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DE Cauwer I, Dufay M, Cuguen J, Arnaud JF. Effects of fine-scale genetic structure on male mating success in gynodioecious Beta vulgaris ssp. maritima. Mol Ecol 2010; 19:1540-58. [PMID: 20345690 DOI: 10.1111/j.1365-294x.2010.04586.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Plant mating systems are known to influence population genetic structure because pollen and seed dispersal are often spatially restricted. However, the reciprocal outcomes of population structure on the dynamics of polymorphic mating systems have received little attention. In gynodioecious sea beet (Beta vulgaris ssp. maritima), three sexual types co-occur: females carrying a cytoplasmic male sterility (CMS) gene, hermaphrodites carrying a non-CMS cytoplasm and restored hermaphrodites that carry CMS genes and nuclear restorer alleles. This study investigated the effects of fine-scale genetic structure on male reproductive success of the two hermaphroditic forms. Our study population was strongly structured and characterized by contrasting local sex-ratios. Pollen flow was constrained over short distances and depended on local plant density. Interestingly, restored hermaphrodites sired significantly more seedlings than non-CMS hermaphrodites, despite the previous observation that the former produce pollen of lower quality than the latter. This result was explained by the higher frequency of females in the local vicinity of restored (CMS) hermaphrodites as compared to non-CMS hermaphrodites. Population structure thus strongly influences individual fitness and may locally counteract the expected effects of selection, suggesting that understanding fine scale population processes is central to predicting the evolution of gender polymorphism in angiosperms.
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Affiliation(s)
- Isabelle DE Cauwer
- Laboratoire de Génétique et Evolution des Populations Végétales, UMR CNRS 8016, Bâtiment SN2, Université des Sciences et Technologies de Lille - Lille 1, F-59655 Villeneuve d'Ascq Cedex, France.
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25
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McCauley DE, Bailey MF. Recent advances in the study of gynodioecy: the interface of theory and empiricism. ANNALS OF BOTANY 2009; 104:611-20. [PMID: 19515690 PMCID: PMC2729626 DOI: 10.1093/aob/mcp141] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2009] [Revised: 03/25/2009] [Accepted: 04/29/2009] [Indexed: 05/08/2023]
Abstract
BACKGROUND In this review we report on recent literature concerned with studies of gynodioecy, or the co-occurrence of female and hermaphrodite individuals in natural plant populations. Rather than review this literature in its entirety, our focus is on the interplay between theoretical and empirical approaches to the study of gynodioecy. SCOPE Five areas of active inquiry are considered. These are the cost of restoration, the influence of population structure on spatial sex-ratio variation, the influence of inbreeding on sex expression, the signature of cyto-nuclear coevolution on the mitochondrial genome, and the consequences of mitochondrial paternal leakage. CONCLUSIONS Recent advances in the study of gynodioecy have been made by considering both the ecology of female:hermaphrodite fitness differences and the genetics of sex expression. Indeed theory has guided empiricism and empiricism has guided theory. Future advances will require that some of the methods currently available only for model organisms be applied to a wider range of species.
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Affiliation(s)
- David E McCauley
- Department of Biological Sciences, Vanderbilt University, Nashville, TN 37235, USA.
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26
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Dufay M, Cuguen J, Arnaud JF, Touzet P. SEX RATIO VARIATION AMONG GYNODIOECIOUS POPULATIONS OF SEA BEET: CAN IT BE EXPLAINED BY NEGATIVE FREQUENCY-DEPENDENT SELECTION? Evolution 2009; 63:1483-97. [PMID: 19222569 DOI: 10.1111/j.1558-5646.2009.00653.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Mathilde Dufay
- Laboratoire de Génétique et Evolution des Populations Végétales, UMR CNRS 8016, Université des Sciences et Technologies de Lille - Lille1, F-59655 Villeneuve d'Ascq cedex, France.
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27
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Del Castillo RF, Trujillo S. Evidence of restoration cost in the annual gynodioecious Phacelia dubia. J Evol Biol 2008; 22:306-13. [PMID: 19032498 DOI: 10.1111/j.1420-9101.2008.01644.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A negative pleiotropic effect on fitness of nuclear sex-determining genes (cost of restoration) could explain nuclear-cytoplasmic gynodioecy but rarely has been demonstrated empirically. In a gynodioecious Phacelia dubia population, maternal lineages produce only hermaphroditic progenies irrespective of the pollen parent (N) or can segregate females (S). Natural progenies of N maternal plants had lower seed viability than that of S. Full-sib progenies of unrelated hermaphrodites from all possible matings between N and S lineages had similar pollen filling but differed in sporophyte performance, mainly at seed germination stage. A discrete multivariate analysis reveals that the performance of N(female symbol) x S(male symbol) progeny at early stages of development was significantly lower than that of the other three types of mating in agreement with the silent-cost-of-restoration hypothesis, affecting the sporophyte. The restoration cost and male sterility appear to be dominant and consequence of nuclear-cytoplasmic incompatibilities that may maintain nuclear-cytoplasmic polymorphism by frequency-dependent selection.
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Affiliation(s)
- R F Del Castillo
- CIIDIR Oaxaca, Instituto Politécnico Nacional, Santa Cruz Xoxocotlán, Oaxaca, Mexico.
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